At present, derailments of a railway vehicle happen occasionally domestic and overseas. An excessive transverse displacement of the train after the train is derailed is apt to cause a rollover of the train, which causes a heavy loss of life and property. Especially on a viaduct, with the limitation of a width of a bridge floor, the train may even fall into a riverway or fall off a cliff if the amplitude of the transverse displacement is excessive, which may cause a severe consequent.
The anti-derailment safety device is designed for avoiding the accidents which are caused by an excessive transverse displacement of wheels after the train is derailed.
A transverse displacement limitation system for a bogie is disclosed in a patent application Publication No. CN 101400559Y. The system is consisted of anti-derailment protection devices placed along inner sides of a pair of rails respectively and a transverse displacement limitation device arranged at a lower portion of the bogie. The transverse displacement limitation device includes a limiter, and the limiter protrudes downward at a position close to the inner side with respect to the wheel of the bogie. When the train runs normally, the limiter does not contact the anti-derailment protection device; and when the train is derailed, the limiter is in a sliding contact with an inner side surface of the anti-derailment protection device.
A transverse displacement limitation device for a bogie is disclosed in a patent application Publication No. CN 102414071A. The device is provided with an anti-derailment protection device along an inner side of the rail and a limiter which is close to the inner side with respect to a wheel of the bogie and is in a sliding contact with the inner side surface of the transverse displacement limitation device. The limiter is provided with a sliding contact portion and a guiding portion. The sliding contact portion has a sliding contact surface which is in a sliding contact with the inner side surface of the anti-derailment protection device. The guiding portion extends respectively from a front portion and a rear portion of the sliding contact portion and has a guiding slope, the guiding slope has a front end inclined towards a direction away from the inner side surface of the anti-derailment protection device and a base in connection with the sliding contact surface. When the train runs normally, the limiter does not contact the anti-derailment protection device; and when the train is derailed, the limiter is in a sliding contact with the inner side surface of the anti-derailment protection device.
The two transverse displacement limitation devices for the bogie can limit the transverse displacement of the derailed bogie in a certain degree, however, the anti-derailment protection device is required to be installed at the inner side of the rail, that is, an auxiliary rail is required. It is equivalent to set two sets of rails, one set of rails is used to support the wheels to realize a running function and the other set of rails is used to cooperate with the limiter to function as a stopper when the train is derailed. This structure is too complicated and the cost is too high, thus it is difficult to realize an industrialized application. In addition, the limiter is located at a center position below the frame, and when the train is derailed, the train has to move transversely by at least one half of the width of the train body to come into contact with the limiter, the transverse displacement is too large and the security protection performance is poor, thus this structure can not meet higher security protection requirements.
A bogie frame for a vehicle is disclosed in a utility model Publication No. CN 203439052A, and includes a side sill, an end sill and a draft sill which are all welded, and further includes an anti-derailment protection strip. The derailment protection strip is connected below the end sill by an installation seat, the installation seat is welded to the bottom of the end sill, and the derailment protection strip is welded on the installation seat.
Compared with the two above manners, the derailment protection strips of this anti-derailment safety device limit the transverse displacement by contacting the rails when the train is derailed, and it is not required to place the auxiliary rails. The derailment protection strips are bilaterally symmetrical and respectively correspond to two rails, and are close to the rails, thus when the train is derailed, the derailment protection strips can come into contact with the rails in a short time and a short distance, which can increase the security protection performance when the train is accidentally derailed.
However, the derailment protection strip has a too complicated structure and a long length, thus occupying too much space below the train and then affecting the arrangement and installation of other underfloor devices. In addition, the derailment protection strip is required to be welded below the end sill by the installation seats at a front end and a rear end of the derailment protection strip, and the installation seat has a box-shaped structure, thus also having defects such as the structure is complicated and the volume is too large.
Thus, on the premise of ensuring the security performance, an urgent technical problem to be resolved by the person skilled in the art is to optimize the design of the anti-derailment safety device.